Electric switch



2 Sheets Sheet 1.

(No Model.)

0. J. MILLER. ELECTRIC SWITCH.

No. 536,221. Patented Mar. 26, 1895.

.FIG.1.

Invent-or Charlasl Miller" 2 Sheets-Sheet 2. O. J. MILLER.

ELECTRIC SWITGH.

(No Model.)

v No. 536,221. Patented Mar. 26, 1895.

VII/l/I/l/A In/ven tm" lzaries LIZ filler by his Jitorzze '5- itiwssea'I UNITED ST TES PATENT OFFICE.

CHARLES J. MILLER, OF PHILADELPHIA, PENNSYLVANIA.

ELECTRIC SWITCH.

SBEGIFIOATION forming part of Letters Patent No.536,221, dated March 28,1895.

Application filed January 19, 1895; Serial Ho. 535,617- (No model.)

' citizen of the United States, residingin Philadelphia, Pennsylvania,have invented' Improvements in Electric Switches, of which the followingis a specification.

The object of my invention is to construct a knife switch in such amanner, that itwill have an instantaneous release from the con- .tact,and thus prevent arcing to a great extent.

My invention relates, also, to the construc-.

tion of the binding post.

' In the accompanying drawings:-Figure 1 is a front view of my improvedknife switch. Fig. 2, is a longitudinal section on the line 2 2, Fig. 1.Fig. 3, is alongitudinal section on the line 3-3, Fig. 1. Fig. 4, is aview showing the first movement of the handle and spring under. tension.Fig. 5, is a View showing the knife released from the contact; and Figs.6 and 7, are views of modifications of my invention.

A is the base of the switch, made of suitable non-conducting material.

B is one terminal, and O is the other minal.

As shown in Figs. 1 and 2, the knife D is pivoted at b to the terminalB, and rests between two spring arms 0 c of the terminal 0, as shown inFig. 3.

The knife in the present instance, as shown in Figs. 1 and 2, is made inthree parts, socured together, two side plates (1 d, and a spacing blockd, and mounted between the two side plates is a spring E, secured to theplates by a rivet or pin e.- The portion e of the spring is reduced, sothat it will yield under pressure, and the end of this spring extendsunder the nose f of the handleF. This handle is pivoted at d to theknife D, and has a suitable stop f, so that the movement indicated inFig. 4 will be limited. The first efiect of movement of the handle inthe direction ofthe arrow, Fig. 2, is to place tension upon thespring-E, as indicated in Fig. 4, and to slightly move the knife in thearms ter- 0 c, and a continued movement from the po sition shown in Fig.4:, will draw the knife from between the arms, and as the knife is drawnfrom between the arms, the spring will shown in Fig. 2, flush with theknife out of a the way, but when it is wished to "operate the knife, thehandle can be moved as shown in Fig. 4, so that it can be properlygrasped and then quickly drawn, and while its construc tion withoutthespring will be much better than the ordinaryknife switch in which thehandle is rigidly secured to the knife, I prefer to construct the switchwith the spring, so that the movement of the knife will be accelerated.e j

It will be understood, that the spring may be arranged in adifierentmanner from that shown in Figs. 1 and 2. For instance the spring may bemounted on the handle, and extend over the knife, as shown in Fig. 6,gaining the same result, or a coiled spring may be substituted for theleaf springg and the knife may be pivoted to the terminal 0 instead ofto the terminal B.

As shown in Fig. 7, the spring may be tapored, so that when it is atrest between the arms of the contact, it will expand the sides of theknife against the arms insuring a perfect contact, and as soon aspressure is applied to the spring, the sides will contract, allowing theknife to be quickly removed from the contact. Each terminal has a jaw i,pivoted at 2'', provided with a set screw 1?. Hence by placing the endof the wire between thejaws, and turningthe screw, the wire is firmlyheld to the terminal.

I claim as my invention- 1. The combination of the terminals,aknifepivoted at one end to one of said terminals, a handle pivoted to theopposite end of the knife, a spring carried by the knife, and extendingunder the handle, and a projection on the handle for placing tensionupon the spring, substantially as described.

2. The combination of the terminals, a knife pivoted to one of saidterminals, a spring mounted in the knife, a handle pivoted to the end ofthe knife, a stop on said handle for limiting its motion independent ofthe knife, and a spring so mounted between the handle and the knife,that the first movement of the handle will place tension upon the springwhich is exerted to accelerate the movement of the knife as it isWithdrawn from the terminal.

3. The combination of the terminals, the pivoted knife having yieldingside plates, a tapered spring adapted to pass between the side platesand to force them out against the contacts, and a pivoted handle actingto with-

